<?php

function utf8_strlen($string) {
    return strlen(utf8_decode($string));
}

function utf8_strpos($string, $needle, $offset = NULL) {
    if (is_null($offset)) {
        $array = explode($needle, $string, 2);

        if (count($array) > 1) {
            return utf8_strlen($array[0]);
        }

        return false;
    } else {
        if (!is_int($offset)) {
            trigger_error('utf8_strpos: Offset must be an integer', E_USER_ERROR);

            return false;
        }

        $string = utf8_substr($string, $offset);

        if (false !== ($position = utf8_strpos($string, $needle))) {
            return $position + $offset;
        }

        return false;
    }
}

function utf8_strrpos($string, $needle, $offset = NULL) {
    if (is_null($offset)) {
        $array = explode($needle, $string);

        if (count($array) > 1) {
            array_pop($array);

            $string = join($needle, $array);

            return utf8_strlen($string);
        }

        return false;
    } else {
        if (!is_int($offset)) {
            trigger_error('utf8_strrpos expects parameter 3 to be long', E_USER_WARNING);

            return false;
        }

        $string = utf8_substr($string, $offset);

        if (false !== ($position = utf8_strrpos($string, $needle))) {
            return $position + $offset;
        }

        return false;
    }
}

function utf8_substr($string, $offset, $length = null) {
    // generates E_NOTICE
    // for PHP4 objects, but not PHP5 objects
    $string = (string) $string;
    $offset = (int) $offset;

    if (!is_null($length))
        $length = (int) $length;

    // handle trivial cases
    if ($length === 0)
        return '';

    if ($offset < 0 && $length < 0 && $length < $offset)
        return '';

    // normalise negative offsets (we could use a tail
    // anchored pattern, but they are horribly slow!)
    if ($offset < 0) {

        // see notes
        $strlen = strlen(utf8_decode($string));
        $offset = $strlen + $offset;

        if ($offset < 0)
            $offset = 0;
    }

    $Op = '';
    $Lp = '';

    // establish a pattern for offset, a
    // non-captured group equal in length to offset
    if ($offset > 0) {

        $Ox = (int) ($offset / 65535);
        $Oy = $offset % 65535;

        if ($Ox) {
            $Op = '(?:.{65535}){' . $Ox . '}';
        }

        $Op = '^(?:' . $Op . '.{' . $Oy . '})';
    } else {

        // offset == 0; just anchor the pattern
        $Op = '^';
    }

    // establish a pattern for length
    if (is_null($length)) {

        // the rest of the string
        $Lp = '(.*)$';
    } else {

        if (!isset($strlen)) {
            // see notes
            $strlen = strlen(utf8_decode($string));
        }

        // another trivial case
        if ($offset > $strlen)
            return '';

        if ($length > 0) {

            // reduce any length that would
            // go passed the end of the string
            $length = min($strlen - $offset, $length);

            $Lx = (int) ( $length / 65535 );
            $Ly = $length % 65535;

            // negative length requires a captured group
            // of length characters
            if ($Lx)
                $Lp = '(?:.{65535}){' . $Lx . '}';
            $Lp = '(' . $Lp . '.{' . $Ly . '})';
        } else if ($length < 0) {

            if ($length < ($offset - $strlen)) {
                return '';
            }

            $Lx = (int) ((-$length) / 65535);
            $Ly = (-$length) % 65535;

            // negative length requires ... capture everything
            // except a group of  -length characters
            // anchored at the tail-end of the string
            if ($Lx)
                $Lp = '(?:.{65535}){' . $Lx . '}';
            $Lp = '(.*)(?:' . $Lp . '.{' . $Ly . '})$';
        }
    }

    if (!preg_match('#' . $Op . $Lp . '#us', $string, $match)) {
        return '';
    }

    return $match[1];
}

function utf8_strtolower($string) {
    static $UTF8_UPPER_TO_LOWER = NULL;

    if (is_null($UTF8_UPPER_TO_LOWER)) {
        $UTF8_UPPER_TO_LOWER = array(
            0x0041 => 0x0061,
            0x03A6 => 0x03C6,
            0x0162 => 0x0163,
            0x00C5 => 0x00E5,
            0x0042 => 0x0062,
            0x0139 => 0x013A,
            0x00C1 => 0x00E1,
            0x0141 => 0x0142,
            0x038E => 0x03CD,
            0x0100 => 0x0101,
            0x0490 => 0x0491,
            0x0394 => 0x03B4,
            0x015A => 0x015B,
            0x0044 => 0x0064,
            0x0393 => 0x03B3,
            0x00D4 => 0x00F4,
            0x042A => 0x044A,
            0x0419 => 0x0439,
            0x0112 => 0x0113,
            0x041C => 0x043C,
            0x015E => 0x015F,
            0x0143 => 0x0144,
            0x00CE => 0x00EE,
            0x040E => 0x045E,
            0x042F => 0x044F,
            0x039A => 0x03BA,
            0x0154 => 0x0155,
            0x0049 => 0x0069,
            0x0053 => 0x0073,
            0x1E1E => 0x1E1F,
            0x0134 => 0x0135,
            0x0427 => 0x0447,
            0x03A0 => 0x03C0,
            0x0418 => 0x0438,
            0x00D3 => 0x00F3,
            0x0420 => 0x0440,
            0x0404 => 0x0454,
            0x0415 => 0x0435,
            0x0429 => 0x0449,
            0x014A => 0x014B,
            0x0411 => 0x0431,
            0x0409 => 0x0459,
            0x1E02 => 0x1E03,
            0x00D6 => 0x00F6,
            0x00D9 => 0x00F9,
            0x004E => 0x006E,
            0x0401 => 0x0451,
            0x03A4 => 0x03C4,
            0x0423 => 0x0443,
            0x015C => 0x015D,
            0x0403 => 0x0453,
            0x03A8 => 0x03C8,
            0x0158 => 0x0159,
            0x0047 => 0x0067,
            0x00C4 => 0x00E4,
            0x0386 => 0x03AC,
            0x0389 => 0x03AE,
            0x0166 => 0x0167,
            0x039E => 0x03BE,
            0x0164 => 0x0165,
            0x0116 => 0x0117,
            0x0108 => 0x0109,
            0x0056 => 0x0076,
            0x00DE => 0x00FE,
            0x0156 => 0x0157,
            0x00DA => 0x00FA,
            0x1E60 => 0x1E61,
            0x1E82 => 0x1E83,
            0x00C2 => 0x00E2,
            0x0118 => 0x0119,
            0x0145 => 0x0146,
            0x0050 => 0x0070,
            0x0150 => 0x0151,
            0x042E => 0x044E,
            0x0128 => 0x0129,
            0x03A7 => 0x03C7,
            0x013D => 0x013E,
            0x0422 => 0x0442,
            0x005A => 0x007A,
            0x0428 => 0x0448,
            0x03A1 => 0x03C1,
            0x1E80 => 0x1E81,
            0x016C => 0x016D,
            0x00D5 => 0x00F5,
            0x0055 => 0x0075,
            0x0176 => 0x0177,
            0x00DC => 0x00FC,
            0x1E56 => 0x1E57,
            0x03A3 => 0x03C3,
            0x041A => 0x043A,
            0x004D => 0x006D,
            0x016A => 0x016B,
            0x0170 => 0x0171,
            0x0424 => 0x0444,
            0x00CC => 0x00EC,
            0x0168 => 0x0169,
            0x039F => 0x03BF,
            0x004B => 0x006B,
            0x00D2 => 0x00F2,
            0x00C0 => 0x00E0,
            0x0414 => 0x0434,
            0x03A9 => 0x03C9,
            0x1E6A => 0x1E6B,
            0x00C3 => 0x00E3,
            0x042D => 0x044D,
            0x0416 => 0x0436,
            0x01A0 => 0x01A1,
            0x010C => 0x010D,
            0x011C => 0x011D,
            0x00D0 => 0x00F0,
            0x013B => 0x013C,
            0x040F => 0x045F,
            0x040A => 0x045A,
            0x00C8 => 0x00E8,
            0x03A5 => 0x03C5,
            0x0046 => 0x0066,
            0x00DD => 0x00FD,
            0x0043 => 0x0063,
            0x021A => 0x021B,
            0x00CA => 0x00EA,
            0x0399 => 0x03B9,
            0x0179 => 0x017A,
            0x00CF => 0x00EF,
            0x01AF => 0x01B0,
            0x0045 => 0x0065,
            0x039B => 0x03BB,
            0x0398 => 0x03B8,
            0x039C => 0x03BC,
            0x040C => 0x045C,
            0x041F => 0x043F,
            0x042C => 0x044C,
            0x00DE => 0x00FE,
            0x00D0 => 0x00F0,
            0x1EF2 => 0x1EF3,
            0x0048 => 0x0068,
            0x00CB => 0x00EB,
            0x0110 => 0x0111,
            0x0413 => 0x0433,
            0x012E => 0x012F,
            0x00C6 => 0x00E6,
            0x0058 => 0x0078,
            0x0160 => 0x0161,
            0x016E => 0x016F,
            0x0391 => 0x03B1,
            0x0407 => 0x0457,
            0x0172 => 0x0173,
            0x0178 => 0x00FF,
            0x004F => 0x006F,
            0x041B => 0x043B,
            0x0395 => 0x03B5,
            0x0425 => 0x0445,
            0x0120 => 0x0121,
            0x017D => 0x017E,
            0x017B => 0x017C,
            0x0396 => 0x03B6,
            0x0392 => 0x03B2,
            0x0388 => 0x03AD,
            0x1E84 => 0x1E85,
            0x0174 => 0x0175,
            0x0051 => 0x0071,
            0x0417 => 0x0437,
            0x1E0A => 0x1E0B,
            0x0147 => 0x0148,
            0x0104 => 0x0105,
            0x0408 => 0x0458,
            0x014C => 0x014D,
            0x00CD => 0x00ED,
            0x0059 => 0x0079,
            0x010A => 0x010B,
            0x038F => 0x03CE,
            0x0052 => 0x0072,
            0x0410 => 0x0430,
            0x0405 => 0x0455,
            0x0402 => 0x0452,
            0x0126 => 0x0127,
            0x0136 => 0x0137,
            0x012A => 0x012B,
            0x038A => 0x03AF,
            0x042B => 0x044B,
            0x004C => 0x006C,
            0x0397 => 0x03B7,
            0x0124 => 0x0125,
            0x0218 => 0x0219,
            0x00DB => 0x00FB,
            0x011E => 0x011F,
            0x041E => 0x043E,
            0x1E40 => 0x1E41,
            0x039D => 0x03BD,
            0x0106 => 0x0107,
            0x03AB => 0x03CB,
            0x0426 => 0x0446,
            0x00DE => 0x00FE,
            0x00C7 => 0x00E7,
            0x03AA => 0x03CA,
            0x0421 => 0x0441,
            0x0412 => 0x0432,
            0x010E => 0x010F,
            0x00D8 => 0x00F8,
            0x0057 => 0x0077,
            0x011A => 0x011B,
            0x0054 => 0x0074,
            0x004A => 0x006A,
            0x040B => 0x045B,
            0x0406 => 0x0456,
            0x0102 => 0x0103,
            0x039B => 0x03BB,
            0x00D1 => 0x00F1,
            0x041D => 0x043D,
            0x038C => 0x03CC,
            0x00C9 => 0x00E9,
            0x00D0 => 0x00F0,
            0x0407 => 0x0457,
            0x0122 => 0x0123
        );
    }

    $unicode = utf8_to_unicode($string);

    if (!$unicode) {
        return false;
    }

    $count = count($unicode);

    for ($i = 0; $i < $count; $i++) {
        if (isset($UTF8_UPPER_TO_LOWER[$unicode[$i]])) {
            $unicode[$i] = $UTF8_UPPER_TO_LOWER[$unicode[$i]];
        }
    }

    return utf8_from_unicode($unicode);
}

function utf8_strtoupper($string) {
    static $UTF8_LOWER_TO_UPPER = NULL;

    if (is_null($UTF8_LOWER_TO_UPPER)) {
        $UTF8_LOWER_TO_UPPER = array(
            0x0061 => 0x0041,
            0x03C6 => 0x03A6,
            0x0163 => 0x0162,
            0x00E5 => 0x00C5,
            0x0062 => 0x0042,
            0x013A => 0x0139,
            0x00E1 => 0x00C1,
            0x0142 => 0x0141,
            0x03CD => 0x038E,
            0x0101 => 0x0100,
            0x0491 => 0x0490,
            0x03B4 => 0x0394,
            0x015B => 0x015A,
            0x0064 => 0x0044,
            0x03B3 => 0x0393,
            0x00F4 => 0x00D4,
            0x044A => 0x042A,
            0x0439 => 0x0419,
            0x0113 => 0x0112,
            0x043C => 0x041C,
            0x015F => 0x015E,
            0x0144 => 0x0143,
            0x00EE => 0x00CE,
            0x045E => 0x040E,
            0x044F => 0x042F,
            0x03BA => 0x039A,
            0x0155 => 0x0154,
            0x0069 => 0x0049,
            0x0073 => 0x0053,
            0x1E1F => 0x1E1E,
            0x0135 => 0x0134,
            0x0447 => 0x0427,
            0x03C0 => 0x03A0,
            0x0438 => 0x0418,
            0x00F3 => 0x00D3,
            0x0440 => 0x0420,
            0x0454 => 0x0404,
            0x0435 => 0x0415,
            0x0449 => 0x0429,
            0x014B => 0x014A,
            0x0431 => 0x0411,
            0x0459 => 0x0409,
            0x1E03 => 0x1E02,
            0x00F6 => 0x00D6,
            0x00F9 => 0x00D9,
            0x006E => 0x004E,
            0x0451 => 0x0401,
            0x03C4 => 0x03A4,
            0x0443 => 0x0423,
            0x015D => 0x015C,
            0x0453 => 0x0403,
            0x03C8 => 0x03A8,
            0x0159 => 0x0158,
            0x0067 => 0x0047,
            0x00E4 => 0x00C4,
            0x03AC => 0x0386,
            0x03AE => 0x0389,
            0x0167 => 0x0166,
            0x03BE => 0x039E,
            0x0165 => 0x0164,
            0x0117 => 0x0116,
            0x0109 => 0x0108,
            0x0076 => 0x0056,
            0x00FE => 0x00DE,
            0x0157 => 0x0156,
            0x00FA => 0x00DA,
            0x1E61 => 0x1E60,
            0x1E83 => 0x1E82,
            0x00E2 => 0x00C2,
            0x0119 => 0x0118,
            0x0146 => 0x0145,
            0x0070 => 0x0050,
            0x0151 => 0x0150,
            0x044E => 0x042E,
            0x0129 => 0x0128,
            0x03C7 => 0x03A7,
            0x013E => 0x013D,
            0x0442 => 0x0422,
            0x007A => 0x005A,
            0x0448 => 0x0428,
            0x03C1 => 0x03A1,
            0x1E81 => 0x1E80,
            0x016D => 0x016C,
            0x00F5 => 0x00D5,
            0x0075 => 0x0055,
            0x0177 => 0x0176,
            0x00FC => 0x00DC,
            0x1E57 => 0x1E56,
            0x03C3 => 0x03A3,
            0x043A => 0x041A,
            0x006D => 0x004D,
            0x016B => 0x016A,
            0x0171 => 0x0170,
            0x0444 => 0x0424,
            0x00EC => 0x00CC,
            0x0169 => 0x0168,
            0x03BF => 0x039F,
            0x006B => 0x004B,
            0x00F2 => 0x00D2,
            0x00E0 => 0x00C0,
            0x0434 => 0x0414,
            0x03C9 => 0x03A9,
            0x1E6B => 0x1E6A,
            0x00E3 => 0x00C3,
            0x044D => 0x042D,
            0x0436 => 0x0416,
            0x01A1 => 0x01A0,
            0x010D => 0x010C,
            0x011D => 0x011C,
            0x00F0 => 0x00D0,
            0x013C => 0x013B,
            0x045F => 0x040F,
            0x045A => 0x040A,
            0x00E8 => 0x00C8,
            0x03C5 => 0x03A5,
            0x0066 => 0x0046,
            0x00FD => 0x00DD,
            0x0063 => 0x0043,
            0x021B => 0x021A,
            0x00EA => 0x00CA,
            0x03B9 => 0x0399,
            0x017A => 0x0179,
            0x00EF => 0x00CF,
            0x01B0 => 0x01AF,
            0x0065 => 0x0045,
            0x03BB => 0x039B,
            0x03B8 => 0x0398,
            0x03BC => 0x039C,
            0x045C => 0x040C,
            0x043F => 0x041F,
            0x044C => 0x042C,
            0x00FE => 0x00DE,
            0x00F0 => 0x00D0,
            0x1EF3 => 0x1EF2,
            0x0068 => 0x0048,
            0x00EB => 0x00CB,
            0x0111 => 0x0110,
            0x0433 => 0x0413,
            0x012F => 0x012E,
            0x00E6 => 0x00C6,
            0x0078 => 0x0058,
            0x0161 => 0x0160,
            0x016F => 0x016E,
            0x03B1 => 0x0391,
            0x0457 => 0x0407,
            0x0173 => 0x0172,
            0x00FF => 0x0178,
            0x006F => 0x004F,
            0x043B => 0x041B,
            0x03B5 => 0x0395,
            0x0445 => 0x0425,
            0x0121 => 0x0120,
            0x017E => 0x017D,
            0x017C => 0x017B,
            0x03B6 => 0x0396,
            0x03B2 => 0x0392,
            0x03AD => 0x0388,
            0x1E85 => 0x1E84,
            0x0175 => 0x0174,
            0x0071 => 0x0051,
            0x0437 => 0x0417,
            0x1E0B => 0x1E0A,
            0x0148 => 0x0147,
            0x0105 => 0x0104,
            0x0458 => 0x0408,
            0x014D => 0x014C,
            0x00ED => 0x00CD,
            0x0079 => 0x0059,
            0x010B => 0x010A,
            0x03CE => 0x038F,
            0x0072 => 0x0052,
            0x0430 => 0x0410,
            0x0455 => 0x0405,
            0x0452 => 0x0402,
            0x0127 => 0x0126,
            0x0137 => 0x0136,
            0x012B => 0x012A,
            0x03AF => 0x038A,
            0x044B => 0x042B,
            0x006C => 0x004C,
            0x03B7 => 0x0397,
            0x0125 => 0x0124,
            0x0219 => 0x0218,
            0x00FB => 0x00DB,
            0x011F => 0x011E,
            0x043E => 0x041E,
            0x1E41 => 0x1E40,
            0x03BD => 0x039D,
            0x0107 => 0x0106,
            0x03CB => 0x03AB,
            0x0446 => 0x0426,
            0x00FE => 0x00DE,
            0x00E7 => 0x00C7,
            0x03CA => 0x03AA,
            0x0441 => 0x0421,
            0x0432 => 0x0412,
            0x010F => 0x010E,
            0x00F8 => 0x00D8,
            0x0077 => 0x0057,
            0x011B => 0x011A,
            0x0074 => 0x0054,
            0x006A => 0x004A,
            0x045B => 0x040B,
            0x0456 => 0x0406,
            0x0103 => 0x0102,
            0x03BB => 0x039B,
            0x00F1 => 0x00D1,
            0x043D => 0x041D,
            0x03CC => 0x038C,
            0x00E9 => 0x00C9,
            0x00F0 => 0x00D0,
            0x0457 => 0x0407,
            0x0123 => 0x0122
        );
    }

    $unicode = utf8_to_unicode($string);

    if (!$unicode) {
        return false;
    }

    $count = count($unicode);

    for ($i = 0; $i < $count; $i++) {
        if (isset($UTF8_LOWER_TO_UPPER[$unicode[$i]])) {
            $unicode[$i] = $UTF8_LOWER_TO_UPPER[$unicode[$i]];
        }
    }

    return utf8_from_unicode($unicode);
}

function utf8_to_unicode($str) {
    $mState = 0;     // cached expected number of octets after the current octet
    // until the beginning of the next UTF8 character sequence
    $mUcs4 = 0;     // cached Unicode character
    $mBytes = 1;     // cached expected number of octets in the current sequence

    $out = array();

    $len = strlen($str);

    for ($i = 0; $i < $len; $i++) {
        $in = ord($str{$i});

        if ($mState == 0) {

            // When mState is zero we expect either a US-ASCII character or a
            // multi-octet sequence.
            if (0 == (0x80 & ($in))) {
                // US-ASCII, pass straight through.
                $out[] = $in;
                $mBytes = 1;
            } elseif (0xC0 == (0xE0 & ($in))) {
                // First octet of 2 octet sequence
                $mUcs4 = ($in);
                $mUcs4 = ($mUcs4 & 0x1F) << 6;
                $mState = 1;
                $mBytes = 2;
            } elseif (0xE0 == (0xF0 & ($in))) {
                // First octet of 3 octet sequence
                $mUcs4 = ($in);
                $mUcs4 = ($mUcs4 & 0x0F) << 12;
                $mState = 2;
                $mBytes = 3;
            } else if (0xF0 == (0xF8 & ($in))) {
                // First octet of 4 octet sequence
                $mUcs4 = ($in);
                $mUcs4 = ($mUcs4 & 0x07) << 18;
                $mState = 3;
                $mBytes = 4;
            } else if (0xF8 == (0xFC & ($in))) {
                /* First octet of 5 octet sequence.
                 *
                 * This is illegal because the encoded codepoint must be either
                 * (a) not the shortest form or
                 * (b) outside the Unicode range of 0-0x10FFFF.
                 * Rather than trying to resynchronize, we will carry on until the end
                 * of the sequence and let the later error handling code catch it.
                 */
                $mUcs4 = ($in);
                $mUcs4 = ($mUcs4 & 0x03) << 24;
                $mState = 4;
                $mBytes = 5;
            } else if (0xFC == (0xFE & ($in))) {
                // First octet of 6 octet sequence, see comments for 5 octet sequence.
                $mUcs4 = ($in);
                $mUcs4 = ($mUcs4 & 1) << 30;
                $mState = 5;
                $mBytes = 6;
            } else {
                /* Current octet is neither in the US-ASCII range nor a legal first
                 * octet of a multi-octet sequence.
                 */
                trigger_error('utf8_to_unicode: Illegal sequence identifier ' . 'in UTF-8 at byte ' . $i, E_USER_WARNING);

                return FALSE;
            }
        } else {

            // When mState is non-zero, we expect a continuation of the multi-octet
            // sequence
            if (0x80 == (0xC0 & ($in))) {

                // Legal continuation.
                $shift = ($mState - 1) * 6;
                $tmp = $in;
                $tmp = ($tmp & 0x0000003F) << $shift;
                $mUcs4 |= $tmp;

                /**
                 * End of the multi-octet sequence. mUcs4 now contains the final
                 * Unicode codepoint to be output
                 */
                if (0 == --$mState) {

                    /*
                     * Check for illegal sequences and codepoints.
                     */
                    // From Unicode 3.1, non-shortest form is illegal
                    if (((2 == $mBytes) && ($mUcs4 < 0x0080)) ||
                            ((3 == $mBytes) && ($mUcs4 < 0x0800)) ||
                            ((4 == $mBytes) && ($mUcs4 < 0x10000)) ||
                            (4 < $mBytes) ||
                            // From Unicode 3.2, surrogate characters are illegal
                            (($mUcs4 & 0xFFFFF800) == 0xD800) ||
                            // Codepoints outside the Unicode range are illegal
                            ($mUcs4 > 0x10FFFF)) {

                        trigger_error('utf8_to_unicode: Illegal sequence or codepoint in UTF-8 at byte ' . $i, E_USER_WARNING);

                        return false;
                    }

                    if (0xFEFF != $mUcs4) {
                        // BOM is legal but we don't want to output it
                        $out[] = $mUcs4;
                    }

                    //initialize UTF8 cache
                    $mState = 0;
                    $mUcs4 = 0;
                    $mBytes = 1;
                }
            } else {
                /**
                 * ((0xC0 & (*in) != 0x80) && (mState != 0))
                 * Incomplete multi-octet sequence.
                 */
                trigger_error('utf8_to_unicode: Incomplete multi-octet sequence in UTF-8 at byte ' . $i, E_USER_WARNING);

                return false;
            }
        }
    }

    return $out;
}

function utf8_from_unicode($arr) {
    ob_start();

    foreach (array_keys($arr) as $k) {
        # ASCII range (including control chars)
        if (($arr[$k] >= 0) && ($arr[$k] <= 0x007f)) {
            echo chr($arr[$k]);

            # 2 byte sequence
        } elseif ($arr[$k] <= 0x07ff) {


            echo chr(0xc0 | ($arr[$k] >> 6));
            echo chr(0x80 | ($arr[$k] & 0x003f));

            # Byte order mark (skip)
        } elseif ($arr[$k] == 0xFEFF) {

            // nop -- zap the BOM
            # Test for illegal surrogates
        } elseif ($arr[$k] >= 0xD800 && $arr[$k] <= 0xDFFF) {
            // found a surrogate
            trigger_error('utf8_from_unicode: Illegal surrogate at index: ' . $k . ', value: ' . $arr[$k], E_USER_WARNING);

            return false;

            # 3 byte sequence
        } elseif ($arr[$k] <= 0xffff) {

            echo chr(0xe0 | ($arr[$k] >> 12));
            echo chr(0x80 | (($arr[$k] >> 6) & 0x003f));
            echo chr(0x80 | ($arr[$k] & 0x003f));

            # 4 byte sequence
        } elseif ($arr[$k] <= 0x10ffff) {

            echo chr(0xf0 | ($arr[$k] >> 18));
            echo chr(0x80 | (($arr[$k] >> 12) & 0x3f));
            echo chr(0x80 | (($arr[$k] >> 6) & 0x3f));
            echo chr(0x80 | ($arr[$k] & 0x3f));
        } else {
            trigger_error('utf8_from_unicode: Codepoint out of Unicode range ' . 'at index: ' . $k . ', value: ' . $arr[$k], E_USER_WARNING);

            // out of range
            return FALSE;
        }
    }

    $result = ob_get_contents();

    ob_end_clean();

    return $result;
}

?>